Single-phase motor.



N. PATENTED FEBill 1908. 0 878,923 I J'Jt WOOD 4 SHEETS-SHEET}. L

1 INVENTGR. Myzw g My; m.maqm mean.

N 7 92 PATENTED P B. 11 1908.

SINGLE PHASHMOTOR. APPLIOATION nun APR. 26.1906.

4 SHEETS-831131 2.

v PATENTED FEB. ,11, 1908. .J. J. WOOD. SINGLE PHASE MOTOR. APPLIOATIQN FILED APB. 26.19%.

4 SHEETS-SHEET 3.

FIG. 10

L INVENTOR:

PATBNTED FEB. 11, 1908.

- J. J. WOOD.

' SINGLE PHASE MOTOR. APPLICATION FILED APR. 26.1906.

I .4 SEEETSSHEET 4,

INVENTORY WITNESSES:

JAMES J. Wool), or roar WAYNE, INDIANA.

SINGLE-PHASE MOTOR.

Specification of Letters Patent.

Patented Feb. 11, 1908.

Application filedllpril 26- 1906. Serial No. 31.3.790-

To all whom it may concern:

Be it known that I, JAMES J. W001), a citizen of the United States, residing in. Fort Wayne, in the county of Allen and State of Indiana, have invented certain new and useful Im roveinents in Single-Phase. l\i[otors,

' of whic the following is'a specification.

This invention relates to a single-phase motor which starts as a commutator motor and operates as an induction motor. The motor is inverted, the rotor being the primary and the stator the secondary. The singlephase current is fed to therotor coils through a commutator at starting, and through collectorrings durin normalrunning. Thesecondary or stator ias itswinding short-circuited upon itself in a, definite line, so as to develop fixed magnetic oles for starting, and its coils are vshOrt-c1rcuited along preferably a plurality oflines for normal running.

In the preferred embodiment of my invention herewith illustrated, the motor 18 adapted to start as an inverted repulsion motor. Accordingly, to attain a high initial starting torque, the axis of the commutator brushes is displaced. from the magnetic axis of the secondary or stator to a sullicient angle to give the required torque.

he motor is adapted preferably to be started by manual control; for this purpose a startmg handle or lever is provided wluch is displaced to one position for starting, and,

when a su'llicient speed has been attained, is thrown to another position for normal running. This handle is connected through suitable intermediaries to the respective brush-holders, so that, in moving it to the starting position, the commutator brushes are applied and the collector brushes are lifted; and in moving it thence to the running position the commutator brushes are lifted and the collector brushes are applied. In the intermediate or stopped position preferably both sets of brushes are lifted.

Figure 1 of the accompanying drawings is mainly a vertical midseetion in the plane of the rotor shaft axis of a motor constructed according to the preferredembodiment ol this invention. Fig. 2 is a transverse section mainlyon the line 2 --2 in Fig. viewer-l from the right, the right-hand end plate and. bearing being removed. The portion of Fig. 2 broken away at the right is in section on the line a: x in Fig. 1. Fig. 3 is a circuit diagram of a two-pole machine, thestator second- .ary being shown as delta-connected. Figs.

4,5 and 6 are vertical longitudinal sections g showing the brush-o eratm'g parts in the stopped, starting an ositions respectively. Figs. 7, 8 and 9 are agmentary t transverse sectional elevations, showing the "I position of the.'brush-holders in the starting,

stopped and running positions respectively. Fig. 10 is a diagram of the rotor and brush.

circuit connections. Fig. 11 is a diagram showing the stator winding Y-connected. Fig. 12 is'a diagram illustrating the conditions of the stator for a fourole machine. Fig. 13 is a winding diagram or a-four-pole stator.

. Let A designate the rotor with its primary 4 windin P.

Let I? desi nate the stator with its secondary win-ding The rotor, and stator have laminated cores formed preferably with slots for-the windings or coils in the usual manner (in Fig. 2 the coils are omitted, and a few of the slots are shown). 1

The motor may have any suitable number of poles; it is shown in Figs. 1 and 2 as a fourpole machine, but to simplify the circuit diagrams, Figs. 3, 10 and 1 1, it is thereshown as a two-pole macl'iine.

The rotor shaft 0 carries a commutator D and (-.(il1 -(-.-t:ors orrings E E. The shaft turns as usual in bearings formed in heads F F attached to the opposite ends of a main frame or casing G, or according to any other usual or suitable mechanical construction.

The rotormay be wound according to any system adapted to the primary of an induction motor and adapted also as the rotor of a commutator motor. Thus it may he arranged like the armature winding of a directcurrent motor. For a two-pole machine it may be wound with a simple gramme winding G, as shown in Fig. 3, its coils having direct connection with the commutator segments; for a multipolar machine this winding will be suitably modified, for example according to the methods well understood in winding the armatures of direct-current multipolar nmcluues. The rotor winding is connected at suitable points with the collector rings E l), this conneetiol'i for a two-pole machine being made with diametrically oppositc connnutator segments, as shown in Fig. 3, and'being modilied in the well under stood manner for a multipolanwinding.

The stator is wound as a three phasaarmature, or according to an y system of winding suitable for the armature ,or secondary of an induction motor, and ada ted when partly open-circuited to develop t e required number'of fixed magnetic poles with which the rotor may react as an inverted repulsion motor in starting. To this end the stator winding is short-cucuited upon itself upon a delinite line at a suitable angle to the line of contact of the commutator brushes. For normal running it is further short-circuited on a second line at an angle to the first, and is preferably symmetrically short-circuited on a plurality of lines, after the manner of the armature of an induction motor. This short circuit ma be e ened or closed by any suitable switc suc i as the switch H, which is shown as a knife-switch having fixed blades 0 a engaged by movable blades 6.

The commutator brushes J J for starting are carried by brush-holders K K of any'suitable kind, each of these being mounted on a movable carrier L. The collector brushes M M are carried by brush-holders N N of any suitable construction, which latter holders also are mounted upon or otherwise suitably connected to the respective carriers L L. The particular construction of the brushholders K N, and the means for insulating them from each other and preferably from the carriers, form no necessary part of the present invention and need not be described.

For startin the motor, a startin handle R is provider, constructed prefera ly as a lever enga ing an oscillatory shaft Q. Whatever be tie mechanical construction, the.

starting handle It should be movable to three positions and be so connected to the respective commutator and collector brushes and to the switch ii that in the startin position of the handle the commutator brus ies K are caused to bear upon the commutator, the collector brushes M are lifted from their respective rings, and the switch H is open; in the running position of the handle the commutator brushes are lifted, the collector brushes are applied to their rings, and the switch is closed; and in the third (preferably intermediate) position of the handle both the commutator and collector brushes are lifted,

and the switch is preferably open. The operating handle may be variously connected to the brushes and switch for communicating to them. the requisite movements when the handle is shifted from one position to another.

In the preferred construction shown, where the handle is a lever fixed to a shaft Q, the brushes are operated by cams on this shaft, and the switch is o erated by its movable meinber being direct y connected to the shaft. The shaft Q extends transversely to the motor under the commutator; at prefer ably its middle it has fixed to it a rollar T to which is directly attached, through'an insulation, the movable member or blades 1) of the-switch; 'At suitable points cams U U are fixed on the shaft for operating the brush= carriers 'L L. These cams are shown as simple collars with a flat face which, in the startmg position, Fig. l, is level, and in the running position, Fig; 6, is uptilted. These cams engage plungers V V which are directly connected to the respective brush-carriers L L, shown best in Fig. 2. ,Eachplunger is pressed downward by a spring 0 and is adjustable in length, its upper portion consisting of a rod or link (I the lower end of which is threaded and screws into the lower part of the plunger, the latter being made nonrotative, as by forming it exteriorly as a polygon and arranging it to move freely in a closelyfitting polygonal socket which is conveniently formed in an inward projection e from the main frame G, as best shown inFig. 2.

To start the motor, the handle R is pressed manually over to the starting osition, Where it is held (preferably against tile stress of a s ring which seeks to throw it back) until t e motor is brought-up to speed or approximately. so. 'While thus held the brushes J are applied to the commutator and the brushes M are lifted from the collector rings, as shown in Figs. 2 and 7, and the switch H is open, as shown in Figs. 1, 3 and 4. Then the\ operator quickly throws the starting leverto the o posite extreme position, as indicated in *ig. 6, thereby lifting the commutatpr brushes and ap lying the collector brushes, as shown in Fig 9,.and closing the switch, as shown in Fig. 6. The stator or secondary coils are thus short-circuited at three points, as in any three-phase winding, the single-phase alternating currents being conducted through the collector rings to the coils of the rotor, so that the motor 0 crates as an inverted induction motor. .0 stop the motor, the controlling handle is moved to the intermediate or stopping position, thereby lifting both sets of rushes, as in Fig. 8.

It is important to provide means for resisting the displacement of the operating handle to the starting position, which is preferably a leaf spring and carries :1. roller,

f, which, in the stopped position, rests, as shown in Fig. 5, in a hollow g of the cam \V. This cam (which is convei iiently made intogrally with the collar T) has on'one side of the hollow g a toe IL, which, as the operating handle is thrown to the starting position, hears downwardly upon the roller f, and flexes the spring, as shown in Fig. 4, so that by the se m ' reaction'of the s ring against this toe a constant stress is a orded tending to restore the o crating handle. In the stop ed position t e spring, by pressing the ro er into the 'hollow'g, resists any effort to turn the shaft in eitherdirection, and so holds then erating lever in the stopped position.

1 he cam W has on the opposite side of the hollow g a projection 't'having an approximately concentric exterior face, which, as the operating lever is turned tothe running position, first expels the roller f from the hollow and then re sents this concentric face against the ro ler, as shown. in Fig. 6, where, by reason of the substantially concentric shape of the face,

the spring pressure has no efiect to turn the shaftv in either direction, and consequently it remains in the running position. shown, by reason of the frictional engagement of the roller With the earn, the frictional engagethe concentric face of 'L and reenter the hol- -clockwise to i) being open-circuited).

low g. i y g It will be understood that the commutator brushes J J are displaced around the cornniutator, with reference to the stator field axis, to the angle suitable for repulsion motor action, which commonly is in the neighborhood of twenty degrees. This is shown in Fig. 3 by the line jj which diverges from the stator field axis 1 y, the latter being established by the short-circuiting of the stator winding between the oints v and w, or, withthe star connection s own in Fig. 11, from the point 1: around clockwise to w and thence to m (the remaining winding from a In Fig. 3 the external circuit wires 7r kt leading to the brushes are shown by dotted lines, to distinguish them from the motor windings; and for greater clcarness the connnutator brushes J J are shown within the segments instead of exteriorly. The exterior circuits are more clearly shown in Fig. 10, which indicates in an elementary manner the rotor circuit connections.

The stator may be wound according to any system which, when the winding is partially open-circuitml, will develop the required number of poles corresponding with the Winding of the rotor but in the preferred embodiment of my invention it is provided with a thre'e phasc Y.connected winding. In a four-pole machine the winding may be such that at a given phasethe currents induced in the stator winding will llow as indicated by the radial arrows in Fig. 12, thereby generating poles along the axes y-g; the radiallines adjacent to the polar axes representing the portions of the winding WhlCh are open-c1-rcuited inorder to develo the poles for repulsion-n1otor starting; his result may be attained by means of a three-coil Winding, eachcoil being distributed according to the number of poles, so that between each pole and the next the winding is equally divided between the three coils. An ,example of a suitable winding for a four-pole machine is given in Fig. 13, which is 'a conventional winding diagram, the radial lines indicating the active ortions of the winding lying in the stator s ots, the inner connections being those at one end, and the outer connections those at the other end of the stator. The three coils are here indicated by a coarse line, a fine line, and a dotted line, respectively; and are Ycon nected. The radii 'yy represent the axes of the magnetic poles of the stator when open-circuited for starting, and the radii jj indicate the positions; of the commutator brushes.

My invention is susceptible of considerable winding short-circuited upon itself on a definite line.

2. In a single-phase motor, a rotor winding provided with both commutator and collector rings, connections for supplying current from an external source to said commutator and collector rings alternatively, a stator winding short-circuited upon itself on a definite line, and a switch in circuit with said stator winding arranged to short-circuit said Winding on a second line at an angle to the first.

3. In a single-phase motor, a rotor winding;

provided with both commutator and collector rings, a set of commutator brushes, a set of collector brushes, connections for supplying current to said brushes from an external source, controlling means adapted to bring.

said brushes alternatively into operation, and a stator winding short-circuitcd upon itself on a definite line.

4. In a single-phase motor, .a rotor winding provid ed with-both commutator and collector rings, a set of commutator.brushes, a set of collector brushes, connections for supplying current to said brushes from an external source, controlling means adapted to bring said brushes alternatively into operation, a stator winding short-circuited upon itself on a definite line, and a switch in circuit with said stator winding arranged. to shortto an external source of current, means mechanically connected to said brushes for bringing them alternativelyinto engagement with said commutator and collector rings respectively, and a stator winding short-circuited on itself on a definite line.

6. In a single-phase motor, a rotor winding provided with both commutator and collector rin' s, two sets of brushes adapted to engage sai commutator and collector rings respectively f connections from both sets of brushes to an external source of current, means mechanically connected to said brushes for bringing them alternatively into engagement with said commutator and collector rings respectively, a stator winding short-circnited on itself on a definite line, and a switch in circuit with said stator winding arranged to short-circuit it on a second line at an angle to the first.

7. A single-phase motor com rising a rotor primary, a stator secondary siort-circuitcd on a definite line, a commutator and collector rings connected to the rotor winding, and means for introducing current from an external source to the rotor through the commutator for starting and through the collector rings for normal running.

8. Asingle-phase motor com risingarotor prima a stator secondary s iort-circuited on a d efinite line, a commutator and collectors for the rotor, commutator and collector brushes, means for liftin the commutator brushes and applying t e collector brushes, or vice versa, and connections for supplying current to said brushes from an alternating current source.-

A single-phase motor com rising a rotor primar a stator secondary s ort-circuitcd on a telinite line, a commutator and collectors for the rotor, commutator and collector brushes; an o )erating handle, means connecting said handle and brushes adapted in the starting position of the handle to apply the commutator brushes and lift the collector brushes, and in the running position of the handle to lift the commutator brushes and apply the colletcor brushes, and connections for supplying current to said brushes from an alternatingcurrent source.

10. A single-phase motor con'iprising a rotor primary, a stator secondary shortcircuited on a definite line, a switch for shortcircuiting the stator on a second line at an angle to the lirst, a commutator and collectors for the rotor, commutator and collector brushes, an operatin handle, means connecting said handle wit 1 the respective brushes and with said switch adapted in the starting position of the handle to apply the commutator brushes and lift the collector brushes and open the switch, and in the running position of the handle to lift the commutator brushes and apply the collector brushes and close the switch, and connections for supplying current to said brushes from an alternating current source.

11. A single-phase motor comprising a stator secondary, a rotor primary having a commutator and collector rin commutator and collector brushes, an o crating handle, means connecting said hand e to said brushes adapted to lift either while apilying the other, and means for pressing said handle from the starting to the stopped position.

12. A single-phase motor comprising a stator secondary, a rotor primary having a con'unutator and collector rings, commutator and collector brushes, an operatin handle, means connecting said handle to sair brushes adapted to lift either set while apilying the other, and yielding means for holding said handle in the stopped position and resisting its displacement to the starting position.

13. A sin le-phase motor comprising a stator secondary, a rotor primary having a commutator and collector rings, commuta tor and collector brushes, an operatin handle, means connecting said handle to said brushes adapted to lift either set while apilying the other, and yielding means for holding said handle in the stopped position and resisting its displacement toward either the starting or running positions.

14. A single-phase motor comprising a stator secondary, a rotor primary having a commutator and collector rings, commuta-- tor and collector brushes, an operatin lever, an oscillating cam-shaft connected thereto, and connections therefrom to the res ective brushes adapted as the shaft is oscillated to lift either set of brushes and apply the other.

15. A sin le-phase motor comprising a stator secon ary, a rotor primary having a commutator and collector rings, commutator and collector brushes, rocking carriers each supporting one connnutator and one-collector brush, an operating handle, and means connecting said handle to said carriers adapted in an intermediateposition of the handle to lift all the brushes, in a starting position of the handle to roclr said carriers to appl the commutator brushes, and in a running position of the handle to oppositely rock said carriers to lift the commutator brushes and apply the collector brushes.

16. A single-phase motor comprising a stator secondary, a rotor primary having a commutator and collector rings, commutator and collector brushes, an operating lespring to restore the I position staccaver, connectionstherefrom to the respective brushes adapted to lift either-set while apply ing the other, lever, and a spring enga ng said cam, reci rocally adapted to a p y the stress of tl ie ever from the starting to the stopped position and resist its displacement from te latter toward either the startin or running position.

17. single-phase motor comprising a rotor having a commutator and collector rings, commutator and collector brushes, an operating lever, an oscillating shaft connected thereto, and connections therefrom for operating the respective brushes, a spring-pressed roller, a cam fixed on said shaft and cooperating with said roller having a hollow entered thereby in the stopped.

back the roller in the starting position, and a projection adapted to expel the roller in moving to the running position and having an approximately concentric outer face receiving the roller in the running position.

18. An alternating-current motor having a rotor winding rovided with both commutator and col ector rings, two sets of brushes adapted to engage 'said commutator and collector rings respectively, an operating handle and connections therefrom. for

shifting the brushes adapted in one position of the handle to lift the collector brushes and apply the commutator brushes, and in an other position to lift the commutator brushes and apfply the collector brushes, and connections om the brushes to an alternating current source.

19. A single-phase motor comprising a rotor provided with a winding connected to a a cam in connection with said i of the lever, a toe adapted to press commutatorand to collector rings, a pol stator winding having a portion: on y} of itsphases short-circuited at starting, confor supplying current from an altervnating current source to the rotor. windin I through phase nections the commutator atstarting an through the collector rings for running, and

means. for short-circuiting all the phases of l the stator winding when the motor is up to speed.

20. A single-phase motor comprisin a rotor provided with a winding connect-e to a commutator and to collector rings, a stator provided with a three-phase windin having two of its terminals connected t'oget er, connections for supplying current from an alternating current source to the rotor wind ing through the commutator'at starting and through the collector rings for running, and means for completely short-circuiting the stator winding for running.

2'1. A single-phase motor comprisin a rotor provided with a winding connecte to a commutator and to collector rin s, a stator provided with a Y-connected t ee-phase winding having two of its terminals connected together, brushes for supplying current from an alternating-current source to said commutator at starting and to said colwitnesses.

JAMES J. WOOD.

Witnesses:

W, H. Cnien'ron, E S. I-iu'nrnve. 

